The chart compares NASA's Ares 1 rocket, which is in development, with adaptations of the existing Evolved Expendable Launch Vehicles, the Atlas 5 and Delta 4, which are currently operated by United Launch Alliance for the U.S. military as well as other customers.

This chart is interesting, but is overly simple, incomplete, and likely to be grossly inaccurate. The $120 million per flight estimated cost of Ares 1 sounds far too good to be true, and I'd guess that the real per-flight cost is two or three times that. Even without any architectural changes, another option that isn’t portrayed here is the SpaceX Falcon 9 Heavy, which is slated to have 29 ton lift capacity for less than $100 million per flight, and be human-rated from its first launch, which could be years earlier than the Ares 1.However, replacing just the booster (Ares 1), with another booster for the Orion is only one option. A more drastic revising of the plan might yield better results. For example, many are pushing for a reconsideration of the whole Ares 1/Ares V and Orion program, potentially accomplishing the same tasks with free-market-obtained launch services on EELV-class boosters (Delta, Atlas and Falcon 9). This has the potential to save a lot of money in per-flight costs, and even more in developmental costs, while also stimulating the commercial market in a way that would likely result in further reduction of costs. In any case, a complete re-appraisal of the lunar program is necessary if we want to be sure that we’re taking the best path to developing a safe, inexpensive and sustainable lunar exploration program.

I don't understand how there is a $3.65 billion development cost for DELTAV Heavy given that this vehicle is already build and flying. Human rating and existing vehicle has been estimated at $600m. Perhaps that development cost an actual figure for how much was spent to get the vehicle flying.

Delta IV Heavy or Atlas V might very well have been viable choices a year or two ago, before the Orion spacecraft was whittled significantly down in size (and capability) so that the underpowered Ares I could loft it. Now that $2 billion has been spent on development and Orion has already been scaled down, it probably makes the most economical sense to stick with the "stick." It's not as pretty as the other launch vehicles, but Ares I should provide higher safety with lower cost per launch (assuming the data is accurate and truthful).

The development cost estimates for upgrading the existing Atlas V and the Delta IV rockets were derived from data in NASA's Exploration Systems Architecture Study, Nov. 2005.

Neither the existing EELVs have the payload capacity to launch the currently envisioned Orion spacecraft to the International Space Station, NASA said in the study. Significant modifications would be needed to the first stage of either EELV, and a new second stage also would be required if NASA chose the Atlas V or the Delta IV as its Crew Launch Vehicle. The estimates basically reflect the cost of upgrading the current EELVs for flying astronauts as opposed satellites.

If the Air Force and Nasa had the same approach to space operations we would already be retrofitting the EELVs for the capsules and manned space flight. Lets not forget that the Atlas vehicle was part of the Gemini program.The US is sorely lagging behind the rest of the world in Commercial Space because it is not willing to fund and operate Cape Canaveral as a Spaceport.However,we have more potential coming with a sucessful flight of a Falcon 9.We could have an Atlas V pad and A Delta IV pad at KSC in place of the current shuttle pads. Then Nasa would not be bogged down by the Air Force's methodology for operational space flight.The Air Force would be happy because it would still have complex 41 for Atlas V and Complex 37 for Delta IV.Space X would have their Falcon 9 on Complex 40.What am I saying here? If we have a vehicle fail folks, we are not out of business and grovelling to a foreign entity to get us in space. If we want to be a leader in space we have to pay the bill! There is no inexpensive easy way out.Some commercial competition could reduce the cost though!!I could go on and on but no one really listens anyway. That is why we are where we are. Leave it to Generals and Politicians without the hands on folks and here we are?I couldn't put my email address in so that is why it says anonymous. (odajedi@yahoo.com)

The Exploration Systems Architecture Study is not a valid source to compare Ares and the EELV systems, as it is fundamentally flawed. Even since 2005, the ESAS appendix for Ares I has been modified, however it has not been released.

I guess its reasonably clear that the Ares I stick will not work and it is all just looking for someone to blame. Likewise, the heavy lift vehicle will never fly. No one will own up to these realities, and as a result the shuttle will fly till 2015.

The Shuttle, to get astronauts in orbit, and the heavy lift adaptation of the Shuttle first stage, to get the big stuff in orbit, are the best options in my opinion. They're just now getting the Shuttle's problems fixed, and they want to stop flying it! Great googly moogly!

With the current estimate of $10K per pound (and that is the lowest estimate), NASA can't seriously think they can get the cost down to 2K per pound. Seriously! How about aiming for 50% reduction?!? Something we can believe in.

Your article “Comparison Chart of Rocket Options” on 02/08/2009 was unfair, inaccurate, biased, and full of "skewed" data. As a Cape worker of over 27 years and 3 programs, I feel Todd Halvorson is a "Professional Idiot". Your "numbers" are phony and "skewed" toward NASA. There are professional risk assessment reports "out there". Mike Griffin "pitched" EELV Atlas V to Congress (for CEV & ISS) BEFORE he became NASA Administrator. AFTER he became NASA Administrator, EELV /Atlas V suddenly became "unsafe" for manned missions. It is OBVIOUS that he was either lying then or lying now. He is taking care of his "NASA buddies". He is obviously lining up his next career. Space Flight or any other flight will NEVER be 100% guaranteed. It SHOULD be safe! Use the professional assessments, not personal opinions. These are available either on the internet, OR through the FOIA (Freedom Of Information Act). Be objective and be fair in your reporting. Unfortunately, to the uneducated public, most public opinion is based solely on news media coverage. To congressmen/women, public opinion is a principal deciding factor for program(s) funding. Remember, they want to get reelected. All we are asking is for the media to be accurate and to be fair in your reporting. We are subscribers / newspaper buyers too!

Thanks for your comment. We appreciate the feedback. The sources for the numbers in the chart are listed on the chart. We'd be happy to publish in this blog any other professional risk assessment reports you can find "out there." Feel free to e-mail them to me and we'll post them.

i keep seeing the phrase that the Atlas-V and Delta-IV were designed to launch satelites not astronauts as that is a disqualifying factor. The first three rockets Americans flew into space, Redstone, Atlas-D and Titan-II, were designed to launch WARHEADS, not astronauts and were converted to do so in a short time and were very successful in spite of lousy early launch records.

The phrase is not a disqualifier. In fact it's a qualifier. It simply is a way of saying that either the Atlas V or the Delta IV would have to be human-rated (as well as upgraded) in order to fly Orion.

The modified missiles Redstone, Atlas-D and Titan II performed well for the mission at hand -- launching astronauts into low Earth orbit. But NASA chose to develop a new rocket, human-rated from the get-go, when the agency was directed to fly astronauts to the moon. That of course was the Saturn 5.

I would like to know the cost per launch (in 2008 dollars)of the Delta II, the Delta IV-M and an Atlas V to compare to these costs. I know they are possible moon rockets, but it would help in understanding the figures.

Any ten year old should be able to add those figures up and realize that something is not right with the quoted Ares-I figure.

And that doesn't include the costs for all the change orders which have been made since those contracts were issued either (many due to Thrust Oscillation I might add).

And that doesn't include the contract costs for the new ML/LUT, the Pad modifications, the VAB modifications, the new LCC systems, new MCC systems or the new manufacturing facilities in both Utah and Louisiana -- all of which must be added before the first fully operational Ares-I will ever be able to fly.

And that also doesn't include any of the NASA overheads for design, development, testing & evaluation. It doesn't cover the costs for the new engine test stands, or the refurbished Apollo/Shuttle test stands, the aerodynamic testing, the analysis of induced environments, the new computers which were required to perform those new analysis, the cost of integration. It certainly doesn't cover the cost for any of the battalions of non-contractor NASA civil servants at all the different centers all supporting this effort.

Wish it was as easy as adding up the Ares I contract values. But unfortunately, it's not. I'll give you just one for instance: the second, second-stage contract won by Boeing includes up to 12 avionics flight units at $114 million a pop. Those are not development costs. Those are production costs.

The $4.6 billion we cited is directly from the GAO via the NASA FY08 budget.

Perhaps you folks should do some more digging on this subject, especially by talking to locals like Ross and others who frequent the NSF forums, and who have the insider knowledge that you seem to need on this subject. Don't be taking NASA's fairy tale numbers (or anyone else's) on face value. You will serve your readers well to report more accurate facts about Ares and the alternatives.

The Ares 1 just seems so delightfully simple next to these other alternatives. A solid fueled device whose basic design has a 28 year track record of launching humans into space. When used on the shuttle the success rate is over 99 percent with no failures in over 20 years. And, in the event of an O-ring failure, the crew might have time to get away from "the stick" before a total catastrophe occurs. There are a couple of reasons I don't like the Falcon 9. The chief among them is that it hasn't even flown once. The other is it's complexity. Does anyone remember the Soviet N-1. A huge Saturn V sized rocket which depended on far too many engines to achieve any reliabality. Thirty-two engines in the first stage! The only propulsion-related launch delays the shuttle currently encounters are from the liquid component of the launch system. I believe simplicity is a very important factor of reliabality.

Is it really the choice of independent engineers and scientists? Isn’t it perhaps the choice of some lobbyists? Sorry, it is difficult to believe these numbers. I know the discussion about the security of solid boosters for a long time. Of course one solid booster is more reliable than a large number of parts of several liquid engines. But if such a part fails, you need not necessarily have a disaster. You may remember this failing J2 of a Saturn V launch. It doesn’t matter.

I'm also confused by either the chart in this article or a comment former administrator Griffin said.

In another article on your website ("Griffin says Ares 1 is two times safer"), Griffin said, "Our probabilistic risk assessment for loss of crew on Ares 1 showed it to be twice as safe -- I repeat, twice as safe -- as a human-rated EELV-derived vehicle." Although, if you look at the chart...it shows Ares I at 1 in 1,100 (which, frankly, I find really hard to believe) and Delta IV as 1 in 1,918 probability for crew loss, which isn't twice as safe. So do we believe the numbers NASA quoted almost 3 years ago...or do we believe Mr. Griffin now? I'm not inclined to do either.

Now if you want to make the case that it is overall crew safety and take into account launch abort g's, then you also must realize is that g's that high are usually just instantaneous and not sustained g-loads - and these maximums could occur only at certain points in flight...usually not lasting for more than a few seconds. And NASA is okay with that. Sure, there are more factors that must be taken into account - but I have a hard time believing that no matter what, a solid is 2x safer.

The other misleading fact is that the Delta IV development costs wouldn't be anywhere near that high. And these performance numbers are based on the current Delta IV Heavy, which is in the process of certifying an upgraded engine. Therefore, the DIV will have much better performance than what is quoted here.

Todd, a suggestion for next time - please explain what all these numbers mean, where you got them, and if they're still valid. I think you're doing a real disservice to people who don't have a significant background in launch vehicles/space exploration.

Ares I is not just a new rocket it is a new concept e.g. there have never been a rocket that had a solid propellant first stage and a LOX/LH2 second stage.Therefore its safety is unpredictable. Space Shuttle when developed had the safety level for a Loss of a Crew as 1 in 2000 flight. In reality we already lost 2 crews in some 120 flights. The reason? Space Shuttle was a new concept.What makes the problem even worse is the mitigation of Thrust Oscillation. This also have never been done in history. It make the rocket even more complicated and therefore its safety even more unpredictable.EELV on the other hand is based on a proven concept with a long flight history.

Therefore in my opinion to say that Ares I twice as safe as a human-rated EELV-derived vehicle is a pure speculation.

The EELVs are already operational, with servicing facilities and launch pads. The Delta IV Heavy is serviced and launched by a total of about 200 people. Because it is assembled horizontally and not fueled until launch, it can be transported to the pad with a rubber tired transporter. CX-37 could certainly be modified to allow crew access. The Ares requires maintaining the entire VAB, the mobile launcher platforms (MLPs), the crawlers, and LC-39.

But the ESAS quashed this advantage by ignoring the existing facilities and deciding that the EELVs would have to use LC-39 instead and that the VAB, MLPs, and LC-39 would all have to be modified and maintained indefinitely to accommodate them, with attendant increases in the cost and personnel. This is inexplicable as the facilities already exist at CX-37 and the Delta is designed to be integrated horizontally, not vertically as in the VAB. It suggests they were looking for costs, not savings.

As for the G-loads for the rare high-altitude abort, these are no higher than for the Soyuz, which we are using, and are acceptable for short periods while lying flat on one's back. Moreover, the contractors weren't asked if they could be reduced.

All the posturing for alternatives is quixotic; Ares I-X is going to fly in July, folks. Falcon 9 is vaporware until it flies.

The "stick" has a great success rate. Its manufacturing is well-known and stable. The only O-ring failure was not even a design flaw; it was a management flaw that pushed the design beyond its limits.

And as Todd mentions, the military rockets were the only ones available early in the program; we would never take those chances today. The Mercury astronauts were pretty brave to get on them (I think the Redstone had a 1:3 failure rate prior to Shepard's launch).

Heck, we wring our hands today over visiting Hubble without a backup vehicle ready, so let's "stick" with the candle that works.

The "candle that works", if you don't count the cost and risk of a vibration problem so severe it is requiring a redesign. The Ares will be very expensive to fly, and I doubt there is sufficient public support to keep this program going at that cost.

The ESAS calculated the Ares failure rate based on the Shuttle, counting each Shuttle launch as two sucessful Ares launches, but they didn't count Challenger. Then they calculated the EELV failure rates based on the failure rate of the Titan IV, with which the EELVs have nothing in common except that they are both ELVs. And although the crew wants the EELVs modified so they can be manually controlled, the inability to control a solid fueled rocket at all once it's lit apparently wasn't a worry. At least the Delta Heavy can be shut down if there's a problem.

I would invite anyone to carefully read the LSAS and ESAS, along with the appendices, and say whether you still think these studies were either rigorous or unbiased.

I have seen Jeff Hanley speak; he seems like a no-nonsense guy with good engineering judgment. But I wonder if, given the choice, he wouldn't have preferred a clean-sheet design like the D-IV-H or Falcon to one that was cobbled together from "existing" parts.

It doesn't take a rocket scientist to figure out that they were neither. They knew the answer before the "study" was started. Who was the chief architect of that study? What company did he work for before coming to NASA? Hmmmm....

Perhaps one small detail about designing rockets. If one increases a rocket motor or a solid booster more than ten per cent, it is not any more an existing part. It can really take you by surprise and is no way to save money. Perhaps you remember the problems with the new main engine of the Ariane V. It is just an example.

They try to compare apples to apples but can't. They are trying to compare a vehicle that hasn't been developed with ones already flying. The projected development costs of the ARES is such a joke. Has NASA ever developed a new vehicle or (space station) for what they projected it would cost? It will cost $6 billion or more to develop AREs. Man-rate the EELVs for LEO missions and develop ARES V for planetary missions.

I cannot for the life of me see how it is valid to base a safety analysis of the "stick" on the performance of the shuttle SRBs. It is as if the only factor in stick safety is that the O-rings don't fail and the propellant burns. Aside from the vibration issues, just getting this top-heavy contraption to fly straight will be a feat.